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People who suffer concussions may be at a higher risk of developing plaques on the brain found in people with Alzheimer’s disease, according to a study featured in the journal Neurology.

The new research released today examines the relationship between concussions and amyloid beta plaques in the brain. While the study couldn’t prove causation, it helps shed light into the possible long-term effects of traumatic brain injuries.

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Trauma's Effect on the Brain
Study author Michelle Mielke, a researcher at the Mayo Clinic, scanned the brains of 589 people ages 70 or older. Of those, 141 had symptoms of mild cognitive impairment. All were asked about whether they’d suffered a concussion in the past.

Researchers found the 17 percent of the 448 people without thinking or memory problems reported a brain injury, while 18 percent of the 141 people with memory problems reported a concussion or other head trauma.

The brain scans reveled no differences among the people without memory and thinking impairments, regardless of past head trauma.

Those with memory and thinking impairments and a history of head trauma, however, had an average of 18 percent more amyloid beta plaques—the hallmark of Alzheimer’s disease—than those with no history of head trauma.

“Interestingly, in people with a history of concussion, a difference in the amount of brain plaques was found only in those with memory and thinking problems, not in those who were cognitively normal,” Mielke said in a statement. “Our results add merit to the idea that concussion and Alzheimer’s disease brain pathology may be related.”

Mielke did note that any relationship between head trauma and amyloid plaque development is likely complex.

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More Research Required
Calling the study’s findings “intriguing,” Keith Fargo, director of publications and outreach for the Alzheimer’s Association, said it raises more questions than it answers and that more studies are needed, particularly long-term ones that follow people throughout their lives.

“It’s an interesting piece of an overall puzzle,” he said. “We’re glad people are doing research in this area. We need to know more about head injury and dementia later in life.”

According to the Alzheimer’s Association, previous research has been linking brain injuries to dementia and other cognitive problems for more than 30 years.

Emerging research in athletes who participate in high-contact sports—football, boxing, hockey, etc.—show that repeated blows to the head make them more likely to develop a specific form of dementia called chronic traumatic encephalopathy.

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